In recent years there have been many attempts electronizing the value information including electronic money and tickets in order to achieve a higher efficiency in distribution systems.
One of such attempts uses a markup description language to define the property of value information, digitally sign thereon by the owner to allow the value information to pass current. Now referring to FIG. 1(a), there is shown a schematic diagram in which a center server 3300 owned by an issuer of the value information issues the electronized value information 3303 to an IC card 3301 of a user, in accordance with the Prior Art. The value information 3303 stored in the IC card 3301 has its property described in a markup language, and digitally signed by the issuer thereof on its entirety in order to protect it against any unauthorized alteration. Referring to FIG. 1(b), there is shown a schematic diagram in which the value information 3303 electronized in accordance with the Prior Art is used with a merchant. The value information 3304 stored in the terminal 3302 of merchant is derived from the value information 3303 stored in the IC card 3301 in addition to certain information indicating the transfer of owner, and is digitally signed by the user in order to protect it against any unauthorized alteration. Since the information is not updated but added, this is a method highly secured against any iniquity including alteration, which may circulate the electronized value information in a secure environment.
Another settlement scheme has been proposed, which uses local wireless communication so-called “Bluetooth” between a portable terminal to which the IC card storing the electronized value information is inserted and the POS terminal of a retail store in order to process the settlement such a payment.
However, in accordance with the Prior Art technology, the data size of the electronic value information may grow each time the value information is transacted, causing inconvenience in processing.
In addition, the Prior Art methods are required for certificates of both parties to be exchanged in order to authenticate the digital signatures at the time of transmitting the electronic value information. This is a problem that the anonymity may not be ensured.
Furthermore, the Prior Art methods have another problem that the prepaid cards or tickets may not be systematically processed because every methods of value information transaction use respective proprietary scheme different each other.
Finally, in the Prior Art methods, since the electronic value information is stored in the IC cards, the data size of the electronic value information is limited. And this is still another problem on the expressiveness of the value information that the multimedia information including images cannot be stored. Also, in the Prior Art methods the other party to communicate with in the Bluetooth environment needs to be identified prior to beginning of settlement process. This may cause a problem that, when a plurality of POS terminals are placed side by side in particular, a certain complex operation such as inputting the identification number of the POS terminal of the other party is needed.